DIVISION OF PRIMATE RESOURCES: BREEDING COLONY MANAGEMENT SERVICES SUMMARY The Washington National Primate Research Center (WaNPRC) houses the largest domestic breeding colony of pigtailed macaques (M. nemestrina). This breeding colony serves as a national resource to investigators who use M. nemestrina as an animal model for human disease. The Breeding Colony Management Service (BCMS) functions to optimize quality and availability of this resource. Intentional breeding strategies are used to increase production and reduce loss to increase the availability of animals. One consideration with regard to quality is the elimination of infectious organisms that could impact animal welfare or interfere with research. Current organisms of concern are simian retrovirus (SRV) and Coccidioides immitis, the causative organism of Valley Fever, and sophisticated efforts are underway to eliminate these organisms from the breeding colony. Another consideration for quality is maintenance of on outbred colony. An extensive pedigree and state-of-the- art breeding management software are used to ensure genetic diversity. Additionally, cutting edge genetic tools are used to genetically characterize the animals in the WaNPRC M. nemestrina breeding colony and investigate the association of MHC haplotype with disease susceptibility.